High chairs are used to seat infants who are too small to be seated in standard chairs. High chairs are typically provided with a tray spanning the arms of the chair in front of the infant. The tray serves to restrain the infant within the chair and provide a horizontal surface for holding food during feedings or toys or the like at other times.
High chair trays are typically provided with release mechanisms to allow the tray to be removed to facilitate placing the infant in the high chair and removing him or her therefrom. These mechanisms generally comprise two latches or detent means, one on each side of the bottom surface of the tray, which are spring biased into corresponding slots or recesses incorporated into the arms of the chair. A plurality of consecutive slots or recesses are usually provided to allow the tray to be adjustable horizontally with respect to the high chair so that the tray can be positioned accordingly with respect to the infant. The latches are generally capable of securing the tray to the chair so as to prevent tipping or movement in the vertical direction when the tray is attached to the chair. The tray release mechanism is hand operable by means of levers or the like connected to or formed as part of each latch or detent. Thus, both hands are generally required to attach the tray to the high chair or adjust the tray horizontally with respect to the high chair. These operations can be difficult considering that they must be performed while at the same time trying to restrain the infant within the high chair.
Thus, it has become desirable to provide high chair trays with release mechanisms comprising a single lever or the like which operates both latch means to enable the tray to be removed or adjusted with one hand, thus freeing up the other hand to deal with the child. Several such release mechanisms are known in the art. For example, U.S. Pat. No. 4,842,331 to Waples, issued Jun. 27, 1989, discloses a mechanism which is operated by a single plunger attached by way of several linkages to the latches connecting the tray to the arms of the high chair. While the plunger rotates the latches to a position wherein the tray is adjustable horizontally with respect to the high chair, both hands are required to disengage the latches from the arms so that the tray can be removed from the high chair. U.S. Pat. No, 4,807,928 to Cone, issued Feb. 28, 1989, discloses a single-hand operable mechanism which comprises a handle connected to two latch members by way of respective pivot plates. The handle is operable in one direction to disengage engagement arms on the ends of the latch members so that the tray can be removed from the high chair, and in the other direction to allow the tray to be adjusted horizontally with respect to the high chair while it is securely attached to the chair. U.S. Pat. No. 4,723,813 to Kassai, issued Feb. 9, 1988, also discloses a slide member operating means operable by one hand. This device comprises an operating button connected by several elements to a hook or operating lever which operates to disengage the operating lever from the high chair support frames, thus allowing the tray to be removed from the high chair. Another one-hand operable high chair tray release mechanism is shown in U.S. Pat. No. 4,582,359, to Wise, et al., issued Apr. 15, 1986, which discloses a handle located at the side of the tray that is operable to withdraw two pegs connected by a peg arm from corresponding holes in the high chair arms so that the tray can be removed.
While these devices offer the advantage of one-handed operation, the multi-element linkages required to connect the operating handles to the latch elements necessitate additional manufacturing and assembly operations and can add to the time and cost required to produce the high chair trays. In addition, since injury to the infant can result from exposed pinch points, linkages and sharp edges, it is often necessary to eliminate such dangers by covering the entire release mechanism or sandwiching it between a bottom cover and the bottom of the tray. This also adds to the cost of the materials used to produce the tray. Furthermore, it is desirable that the tray be securable to the high chair during horizontal adjustment thereof to prevent it from being tipped by the infant or by other causes.
Moreover, while some existing release mechanisms provide the convenience of one-hand operation, the handles or levers are located at a discrete location along the periphery of the tray, requiring grasping of the tray at only that location. Furthermore, existing handles or levers require movements of the hand and fingers which do not coincide with the gripping motion typically required to hold and transport the tray with one hand.